Four of your five minidumps point to ntkrnlpa.exe which is a driver in the Windows Operating System. In my research it is often due to faulty RAM or PSU. How many passes did you do with MemTest.
Your other minidump pointed to a Bug Check of 24.
Stop 0x00000024 or NTFS_FILE_SYSTEM
The Stop 0x24 message indicates that a problem occurred within Ntfs.sys, the driver file that allows the system to read and write to NTFS file system drives. A similar Stop message, 0x23, exists for the file allocation table (FAT16 or FAT32) file systems.
Possible Resolutions:
Malfunctioning SCSI and Advanced Technology Attachment (ATA) hardware or drivers can also adversely affect the system's ability to read and write to disk, causing errors. If using SCSI hard disks, check for cabling and termination problems between the SCSI controller and the disks. Periodically check Event Viewer for error messages related to SCSI or FASTFAT in the System log or Autochk in the Application log.
Verify that the tools you use to continually monitor your system, such as virus scanners, backup programs, or disk defragmenters are compatible with Windows XP. Some disks and adapters come packaged with diagnostic software that you can use to run hardware tests.
To test hard disk or volume integrity:
Method 1:
In the Run dialog box, in the Open box type:
cmd
Start the Chkdsk tool, which detects and attempts to resolve file system structural corruption. At the command prompt type:
chkdsk drive: /f
Method 2:
Double-click My Computer, and then select the hard disk you want to check.
On the File menu, click Properties.
Click the Tools tab.
In the Error-checking box, click Check Now.
In Check disk options, select the Scan for and attempt recovery of bad sectors check box. You can also select the Automatically fix file system errors check box.
If the volume you are checking is in use, a message asks whether you want to delay disk error checking until the next time you restart your computer. After you restart, disk error checking runs and the volume chosen is not available to run other tasks during this process. If you cannot restart the computer due to the error, use safe mode or Recovery Console.
If you are not using the NTFS file system, and the system partition is formatted with the file allocation table (FAT16 or FAT32) file system, long file name (LFN) information can be lost if hard disk tools are started from an MS-DOS command prompt. A command prompt appears when using a startup floppy disk or when using the command prompt startup option on multiple boot systems that use FAT16 or FAT32 partitions with Microsoft® Windows® 95 OEM Service Release 2 (OSR2), Microsoft® Windows® 98, or Microsoft® Windows® Millennium Edition (Me) installed. Do not use tools meant for other operating systems on Windows XP partitions!
Nonpaged pool memory might be depleted, which can cause the system to stop. You can resolve this situation by adding more RAM, which increases the quantity of nonpaged pool memory available to the kernel.
